Biographical SketchDr. Nadarajah Vasanthan( Nad) received his B.S (Hon) in chemistry at University of Jaffna, Sri Lanka and his Ph.D. from City University of New York with Prof. Arthur Woodward working in the field of crystallization and spectroscopy of polymers. He was a Postdoctoral Associate at North Carolina State University with Prof. Alan Tonelli where he conducted research in the area of inclusion compounds and solid state NMR spectroscopy. Dr. Nadarajah Vasanthan held research Scientist and senior scientist positions at AlliedSignal and TRI/Princeton, where he studied crystallization and vibrational spectroscopic characterization of oriented polymers. He joined the faculty of chemistry at Long Island University in the fall of 2004 and he is currently serving as an Associate Professor of chemistry. Professor Nad has been teaching various general, physical, inorganic and polymer chemistry courses at both graduate and undergraduate levels. He has published more than fifty peer reviewed article and presented extensively in scientific conferences.

Research Interest
Research in our group is in the general area of polymer science, crystallization and spectroscopic characterization of polymers. Our primary objective is to study the effect of hydrogen bonding in extensibility of hydrogen bonded polymers. Our second objective is to investigate crystallization and degradation behavior of various biodegradable polymers and their nanocomposite systems.

It is generally believed that hydrogen bonding makes polyamides important engineering plastics, because of the high strength it imparts. However, the interchain hydrogen bonds between amide groups are seen as a barrier to ultradrawing of high molecular weight polyamides and, therefore, to the achievement of high strength and high modulus fibers. The purpose of our research is to develop a new method to spin and draw high strength fibers and films by suppressing the interchain amide group hydrogen bonding. There is evidence in the literature that hydrogen bond suppression can be achieved by Lewis Acid - Base complexation of polyamides, and this may provide a way to temporarily eliminate hydrogen bonding during drawing, allowing orientation to the desired degree, followed by reformation of the hydrogen bonds in the oriented state. We are investigating the influence of hydrogen bonding on fiber formation in low and high molecular weight polyamides, and examine morphological characteristics such as molecular orientation in the crystalline and noncrystalline regions, degree of crystallinity and crystallite size.

Our second objective is to investigate new approaches to significantly improve the performance of poly(lactic acid) (PLA) derived materials and offer a biodegradable alternative for high performance fiber applications. The broad application of current commercial PLA products for semicrystalline, thermoplastic fiber markets is limited by their relatively low Tg (ca. 50-60oC), poor melt strength, low modulus, and unfavorable rate of hydrolysis above the Tg. Thus PLA-based materials have been targeted for predominantly biomedical applications from surgical sutures to drug delivery systems. We plan to address these limitations and expand the use of PLA by preparing hybrid inorganic nanocomposites of PLA with, for example, clays, sol-gels, and metal oxides. We are investigating the effect of microstructure of PLA and PLA nanocomposites on hydrolytic and enzymatic degradation.